Travel classes

Can I upgrade to First Class with French Rails - SNCF TGV?

What travel classes are available with French Rails - SNCF TGV?

What travel classes are available on EuroCity Italy-Switzerland trains with French Rails - SNCF TGV?

What travel classes are available on Trenitalia Intercity Night trains with French Rails - SNCF TGV?

What travel classes are available on Trenitalia Leonardo Express trains with French Rails - SNCF TGV?